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SHOW [GLOBAL|SESSION] VARIABLES

This statement shows a list of variables for the scope of either GLOBAL or SESSION. If no scope is specified, the default scope of SESSION will apply.

Synopsis

ShowStmt:

ShowStmt

ShowTargetFilterable:

ShowTargetFilterable

GlobalScope:

GlobalScope

Examples

mysql> SHOW GLOBAL VARIABLES LIKE 'tidb%';
+------------------------------------+---------------+
| Variable_name                      | Value         |
+------------------------------------+---------------+
| tidb_current_ts                    | 0             |
| tidb_wait_split_region_timeout     | 300           |
| tidb_query_log_max_len             | 2048          |
| tidb_mem_quota_indexlookupjoin     | 34359738368   |
| tidb_index_join_batch_size         | 25000         |
| tidb_index_lookup_concurrency      | 4             |
| tidb_hash_join_concurrency         | 5             |
| tidb_mem_quota_mergejoin           | 34359738368   |
| tidb_checksum_table_concurrency    | 4             |
| tidb_projection_concurrency        | 4             |
| tidb_ddl_reorg_priority            | PRIORITY_LOW  |
| tidb_batch_delete                  | 0             |
| tidb_batch_insert                  | 0             |
| tidb_optimizer_selectivity_level   | 0             |
| tidb_backoff_lock_fast             | 100           |
| tidb_enable_streaming              | 0             |
| tidb_config                        |               |
| tidb_retry_limit                   | 10            |
| tidb_force_priority                | NO_PRIORITY   |
| tidb_ddl_reorg_worker_cnt          | 16            |
| tidb_index_serial_scan_concurrency | 1             |
| tidb_index_lookup_join_concurrency | 4             |
| tidb_constraint_check_in_place     | 0             |
| tidb_scatter_region                | 0             |
| tidb_mem_quota_topn                | 34359738368   |
| tidb_check_mb4_value_in_utf8       | 1             |
| tidb_hashagg_partial_concurrency   | 4             |
| tidb_index_lookup_size             | 20000         |
| tidb_max_chunk_size                | 1024          |
| tidb_disable_txn_auto_retry        | 1             |
| tidb_build_stats_concurrency       | 4             |
| tidb_auto_analyze_ratio            | 0.5           |
| tidb_general_log                   | 0             |
| tidb_ddl_reorg_batch_size          | 1024          |
| tidb_wait_split_region_finish      | 1             |
| tidb_skip_utf8_check               | 0             |
| tidb_opt_agg_push_down             | 0             |
| tidb_auto_analyze_start_time       | 00:00 +0000   |
| tidb_distsql_scan_concurrency      | 15            |
| tidb_mem_quota_sort                | 34359738368   |
| tidb_opt_write_row_id              | 0             |
| tidb_enable_table_partition        | 0             |
| tidb_auto_analyze_end_time         | 23:59 +0000   |
| tidb_mem_quota_nestedloopapply     | 34359738368   |
| tidb_hashagg_final_concurrency     | 4             |
| tidb_slow_log_threshold            | 300           |
| tidb_mem_quota_query               | 34359738368   |
| tidb_snapshot                      |               |
| tidb_dml_batch_size                | 20000         |
| tidb_slow_query_file               | tidb-slow.log |
| tidb_opt_insubquery_unfold         | 0             |
| tidb_mem_quota_indexlookupreader   | 34359738368   |
| tidb_mem_quota_hashjoin            | 34359738368   |
+------------------------------------+---------------+
53 rows in set (0.01 sec)

mysql> SHOW GLOBAL VARIABLES LIKE 'time_zone%';
+---------------+--------+
| Variable_name | Value  |
+---------------+--------+
| time_zone     | SYSTEM |
+---------------+--------+
1 row in set (0.00 sec)

MySQL compatibility

This statement is understood to be fully compatible with MySQL. Any compatibility differences should be reported via an issue on GitHub.

See also